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Updated: Jun 6, 2026

Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Heterogenised N-heterocyclic carbene complexes: synthesis, characterisation and application for hydroformylation and
Sarim Dastgir1, Karl S Coleman, Malcolm L H Green
1Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, UKOX1 3QR. sarim.dastgir@lmh.oxon.org
Abstract:
The imidazolium salts: 1-mesityl-3-(3-trimethoxysilylpropyl)imidazolium iodide and 1-tert-butyl-3-(3-trimethoxysilylpropyl)imidazolium iodide, abbreviated as (tmpMes)HI (3a) and (tmp(t)Bu)HI (3b), respectively, have been synthesised. The palladium(ii) complexes (η(3)-C(3)H(5)) (tmpMes)PdCl (5a) and (η(3)-C(3)H(5))(tmp(t)Bu)PdCl (5b), rhodium(i) and iridium(i) complexes (η(4)-1,5-COD) (tmpMes)MCl, M = Rh (6a), Ir (7a) and (η(4)-1,5-COD)(tmp(t)Bu)MCl, where M = Rh (6b), Ir (7b), were synthesised by silver transmetallation reactions using the silver(i) complexes (tmpMes)AgI (4a) and (tmp(t)Bu)AgI (4b). The iridium complex 7b has been structurally characterised. The Pd(ii) and Rh(i) complexes have been immobilised by attachment to chemically modified MCM-41. The immobilised palladium(ii) materials have been tested as recyclable catalysts for Suzuki type C-C bond formation reactions in water and the immobilised rhodium(i) materials have been examined for their catalytic ability for the hydroformylation of 1-octene.
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